The present invention relates to an image generation method, a program, and an information storage medium.
An image generation device (game system) that is known in the art generates an image as seen from a virtual camera (a given viewpoint) in an object space that is a virtual three-dimensional space, making it highly popular for enabling players to experience a virtual reality. Taking an image generation system that enables players to enjoy a gun-fighting game, by way of example, the player uses a handgun-shaped controller (shooting device) that is shaped in the form of a gun to shoot at target objects such as enemy characters (objects) that appear on a screen, thus enjoying a three-dimensional game that enables repeated fighting with enemy characters.
The controller is not limited to a handgun-shaped controller; it is also possible to conceive of a three-dimensional game in which the player uses a weapon such as a sword or saber as a manipulation input section to exchange blows with an enemy character on the screen. In such a case, it is necessary to have an input interface (input device and detection device) for inputting realistic slashing motions with respect to the enemy character on the screen, in order to increase the feeling of a virtual reality to the player. This input interface has to detect factors such as the position and orientation of the sword wielded by the player.
One method that could be considered for implementing such an input interface is to provide sensors in various parts of the sword-shaped controller and determine the position and orientation of the sword as the manipulation situation of the player from detection information from the sensors, by way of example.
However, this method could have disadvantages that adversely affect the reality in that the controller that is manipulated by the player as the input interface is expensive and heavy. In addition, there is the problem of bad detection accuracy. It is also necessary to provide wiring for supplying the detection information to the system side, which impairs operability and this could reduce the fun and interest of battling with the enemy character.